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Janesville, WI weather and climate

Rock County, WI · population 65,813 · about 863 ft elevation

Everything below is a 30 year average for 1991-2020, computed from daily climate history at Janesville's own coordinates.

The year at a glance

Sunny days
182
clear or partly cloudy, per year
Precipitation
35 in
per year
Wet days
124
rain or snow per year
Snowfall
37 in
per year
Hot days
12
above 90 °F
Freezing nights
147
at or below 32 °F
Humidity
71%
average relative
Average temperature
48 °F
year round

Monthly temperatures

Average daily high and low for each month, in °F.

Daily highDaily low
255075JanMarMayJulSepNovDaily high, Jan: 28 °FDaily high, Feb: 32 °FDaily high, Mar: 44 °FDaily high, Apr: 58 °FDaily high, May: 69 °FDaily high, Jun: 79 °FDaily high, Jul: 83 °FDaily high, Aug: 81 °FDaily high, Sep: 75 °FDaily high, Oct: 61 °FDaily high, Nov: 46 °FDaily high, Dec: 33 °FDaily low, Jan: 11 °FDaily low, Feb: 15 °FDaily low, Mar: 25 °FDaily low, Apr: 36 °FDaily low, May: 48 °FDaily low, Jun: 58 °FDaily low, Jul: 62 °FDaily low, Aug: 59 °FDaily low, Sep: 51 °FDaily low, Oct: 39 °FDaily low, Nov: 28 °FDaily low, Dec: 18 °F
View monthly temperatures as a table
Monthly temperatures (°F)
CityJanFebMarAprMayJunJulAugSepOctNovDec
Daily high283244586979838175614633
Daily low111525364858625951392818

Monthly precipitation

Total rain plus melted snow for each month, in inches.

0.02.04.0JanMarMayJulSepNovJanesville, Jan: 1.8 inJanesville, Feb: 1.7 inJanesville, Mar: 2.4 inJanesville, Apr: 4.0 inJanesville, May: 3.9 inJanesville, Jun: 4.1 inJanesville, Jul: 3.3 inJanesville, Aug: 3.6 inJanesville, Sep: 3.3 inJanesville, Oct: 2.8 inJanesville, Nov: 2.2 inJanesville, Dec: 2.0 in
View monthly precipitation as a table
Monthly precipitation (inches)
CityJanFebMarAprMayJunJulAugSepOctNovDec
Janesville1.81.72.44.03.94.13.33.63.32.82.22.0

Monthly sunny days

Days each month with clear or partly cloudy skies.

01020JanMarMayJulSepNovJanesville, Jan: 12 daysJanesville, Feb: 12 daysJanesville, Mar: 14 daysJanesville, Apr: 13 daysJanesville, May: 15 daysJanesville, Jun: 16 daysJanesville, Jul: 20 daysJanesville, Aug: 20 daysJanesville, Sep: 19 daysJanesville, Oct: 16 daysJanesville, Nov: 14 daysJanesville, Dec: 12 days
View monthly sunny days as a table
Monthly sunny days (days)
CityJanFebMarAprMayJunJulAugSepOctNovDec
Janesville121214131516202019161412

Compare Janesville with another city

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About this data

Figures are 30 year averages for 1991-2020. Wet days count days with measurable precipitation, calibrated against the wet day counts in NOAA's published climate normals. Sunny days count clear plus partly cloudy days, defined as average cloud cover of 63 percent or less and calibrated against NOAA's published sky cover tables. Snowfall figures are model estimates anchored to NOAA station measurements near each city.

Weather data by Open-Meteo.com (CC BY 4.0). Contains modified Copernicus Climate Change Service information (ERA5, ERA5-Land).